Add delete method on databox repositories to invalidate cache on delete

lib/Alchemy/Phrasea/Databox/ArrayCacheDataboxRepository.php

@@ -62,6 +62,16 @@ class ArrayCacheDataboxRepository implements DataboxRepository
         return $this->repository->save($databox);
     }
 
+    /**
+     * @param \databox $databox
+     */
+    public function delete(\databox $databox)
+    {
+        $this->clear();
+
+        return $this->repository->delete($databox);
+    }
+
     /**
      * @param $host
      * @param $port